Electric-railway system



June 14, 1927.

J. A. JACKSON vELEC'IRIC RAILWAY SYSTEM Filed Aug. 26. 1925 Inventor:

L., 2 o e Sa J u v A H m a d 7 trains of cars.

.25 way a system, alternat ng current motorrelatively high irequencytooperate'the al 35 are fed from 40 the trains on the branch tracks whenthe bya variable speed CIiI-ect'current motor 16 n5 track. locating theinterlocking switches natingjcurrent generator also is energized 0Patented June 14, 1927. v I I 1 32 6 5 U ITED S ES AT NT OFF CE JAMES-A;1'.TAoKs0N, or sonnnn'c'ranniunw; Yoiax, AssIeNon T0 GENERAL ntno'rmcCOMPANY, A conronnrrronjor new yonx.

ELECTRIC-RAILWAY sYs'rmvr. 7 Application. filed Angu st 26, 1925. SerialNo. 52,661.

This invention relates to electri'c railway thermore, in accordance withmy invention systems, particularly alternating current I provideautomatic switch mechanism for electric railway systems suitable for.handisconnecting the power source from the dling mail; parcels; orfreight, in which branch track just before the first'ca-r of a 5 trainsof motor-driven cars areoper'ated autrain fed therefrom reaches the maintrack; 6

tomatically without operators or motormen This prevents interconnectionof the branch on a normally energized main track to which track sourcewith the main track source they are fed from branchtracks, under thethrough the train power conductorsregard' control of operators locatedexternal to the less of the number of cars inthe train.

' In the accompanying drawing thesingle The invention hasjfor itsobjectthe pro-- figure diagrammatically illustrates my in vision Jotimprovements in electric railway vention embodied in an automaticalternatsystems otthe'above character for automatiing current electricrailway system having a clly insuring the safe dispatching of'trainsnormally deenergiz'ed branch track joining a 5 of cars from the branchtracks to the main normally energized main track although the track.invention is applicable to other types of elec- While not limitedthereto, the invention is tric railway systems. P of particular utilityWhen'LlSBCllIlj an auto- In the drawing the main trackM is armaticelectric railway system of the type ranged to carry alternating currentmotor described and claimed inthe co-pen ding patdriven cars from theleft to the right and ent application of Robert H. McL'a-in, No. thebranch track B joins with the vmain 751,228, filed November 21', 1924:,and .astrack as shown. The power conductor T signed to the assignee ofmyvzpresen't invenof the main track' is normally energized tion. Int-heMcLain type of automatic railfrom an alternating current source 10 0tdriven cars are assembled into trains and ternating currentmotor-drivencars thereon dispatched from branch loading tracksenatafrelatively high speed. The-power conergizedtroin a variablefrequency source to ductor T of the branch track Bis arranged the maintrack which is normally(energized to be energized from an alternatingcurrent from an alternatingcurrent source ofrelasource of variablefrequency 11 throughthe tively high constant frequency. electromagneticswitch12, the manually op In such'an automatic electric railwaysyserated switch 13 and the automatic switch 'tem my inventionprovidesautoinatic means niechanismlt. v. i p for preventing collisionswhen trains of cars The alternating current" source of varihe branchtracks to the main able frequency 11 in' the form 'shown' is of track,and also insures against inter-connecthe type described in thepreviously mention of the high frequency source normally tioned patentapplication of Robert HfMc-Y energizing the main track with the[variable .Lain, No. 7515228, and comprises an alterfrequency sourceemployed in accelerating nating current generator 15*which is' driven 1trains of cars are fed to the main track. V The motor 16 is suppliedwith power from In carrying the invention into effect in an the directcurrent supply lines 17 and the automatic electric railway. system ofthe speed of the motor is varied by means of the type described intheabove McLain, appli rheostat. 18 which is connected in the motor cationI provide. automatic interlocking field circuitand arranged for-eithermanual in", switch mechanism for preventing energizaoperation orautomatic operation by the 1110- tion of," the accelerating sections ofthe tor '18? as will be morefullydescribed in V i'branch track whentrains of cars are passconnection with the operation of the railway ingover predetermined sections of the main system. The'field winding 19ot'the alterat proper sections of the main track the-posfrom thedirectcurrent supplylines 17 and sibility-vof accelerating and feeding a trainthe exciting current ofthe generator 15 is V or cars from the branchtrackto the main suitably variedxthrough the agency of the track intothe path of an on-com ngtrain of field rh eostat 20.

cars thereonis effectively eliminated jFin- The electromagnetic switchl2 is energized U M I III from suitable supply lines 21 and is under thecontrol of the several car operated interlocking switches which arelocated along the main track M to be operated by the cars passingthereover. Each of the car operated switches 22 is biased to the circuitclosing position as shown so as to normally energize the electromagneticswitch 12 from the supply lines 21. When any one of these interlockingswitches is operated to the open position by a passing car theenergizing circuit ot the electromagnetic switch 12 is in terrupted.

The automatic switch. mechanism 14 in the form shown comprises a pair ofsepa ratcly operable electron'iagnetio switches 23 and 24; which,however, are mechanically interlocked so that when one switch is closedthe other switch is prevented from operating to the closed position. Thecontact 25 of the electromagnetic switch 23 in its uppercircuit-controlling position in which it is shown connects the powerconductor T of the branch track B to the variable frequency power source11, while the contact 26 of the electromagnetic switch 2st in its upperposition connects the power conductor T directly to the normallyenergized power conductor T of the main track M. The operating windingof each of the electromagnetic switches and 24 is electricallyinterlocked with the other switch so that each switch can be energizedonly when the other Switch is in its lower position. The energizingcircuits for the operating windings of both of the electromagneticswitches 23 and 24 are under the control of the two-position,parallelconnected interlocking control switches 27 and 28, which arelocated along the branch track B adjacent to the junction thereof withthe main track M. Each of the twoposition interlocking switches 27 and28 is suitably biased to the circuit-closing position in which it isshown and provided with suitable mechanism for engaging with the carsfed from the branch track B to the main track M to operate the controlswitches to their other circuit-closing positions.

iVith the power conductor T of the main track M normally energized fromthe high frequency source and the control switches 27 and 28 in theirrespective biased positions in which they are shown, the operatingwinding of electromagnetic switch 23 is normally energized through acircuit extending t'rom themain track power conductor T through theconductor 31, the operating wii'iding of switch 23, contact 26 of switch21 in its lower position, conductor 32, and .in parallel circuit throughthe contacts of the control switches 27 and 28 to the track rails whichconstitute the return conductor for both the main track M and the branchtrack B. Thus the electromagnetic switch 23 is normally energized andmaintained operated to the circuit-closing positionin which it is shownin the drawing.

With the electromagnetic switches 12 and 23 in their respectivecircuit-closing positions in which they are shown, the power conductor Tof the branch track B is encrgized from the variable frequency source 11upon closure of the manually operable Switch 13. Upon energization ofthe power conductor T the driving motors ot the cars which may be uponthe branch track B are operatively energized to move the cars toward themain track M. By operating the rheostat 18 to decrease the fieldexcitation of the motor 16, the speed of the alternating currentgenerator may be gradually increased to increase the frequency of thealternating current supplied to the branch track power conductor T andthereby accelerate the motor-driven cars on the branch track B toapproximately the normal running speed of the -ars on the main track M.

In case a car, or train of cars, should be accelerated on the branchtrack B and fed therefrom to the main track into the path of an oncomingcar. or train oi cars. on the main track. a collision would beinevitable. However, this is prevented in accordance with my inventionthrough the engagement of one of the suitably spaced interlockingswitches 22 by the oncoming car or cars on the main track. The resultingopening of the interlocking switch 22 interrupts the energizing circuitof the electromagnetic switch 12 and the latter at once operates to theopen position in accordance with its bias. The opening of switch 12etl'ectively prevents connection of the source 11 to the branch trackpower conductor T upon closure of switch 13 or serves to disconnect thevariable voltage source 11 from the power conductor T of the branchtrack l) and thereby deenergize the driving motors of the cars thereonin case the switch 13 was previously closed. Upon the deenergization otthe driving motors of the cars on the branch track the electromagneticbrakes ordinarily associated therewith soon bring the cars to rest. Itthe rheostat 18 has been operated to increase the speed ot the drivingmotor .16 sutliciently to engage the contact segment 29. an energizingcircuit for the operating motor 18 of the rheostat 18 is establishedupon the operation of the switch 12 to disconnect the generator 15 fromthe track power conductor T the circuit extending from the supply lines17 through the auxiliary contact with which switch 12 is provided. Motor18 at once returns the rhcoslat 18 to the low speed position.

After the oncoming car on the main track M has passed by each of theinterlocking switches 22, these switches return to their respectivebiased positions and reestablish i the energizingcircuit for theclectromagnetic switch 12.

ot swit'ch 121powerthen may be suppliedposition in which it' is shown toUpon the resulting closure from the variable-frequency source 11 to thedriving motorsot the cars on the branch track B to safelyaccelerateand'ieed the cars to the main track M. Since the speed of motor 16 hasbeen automatically reduced to the minimum value through operation ofthemotor 18 thefrequency of the alternating current generator 15likewise is reduced to the minimum value preparatory to restarting andaccelerating the cars on the branch track B. y a I c -As the cars on thebranch track, B approach the main track M, the first carin thetrainengages with the control switch 27and operates the same from thecircuit closing its upper circuit closing position; This, however, doesnot interrupt the energizing circuit or the electromagnetic switch 23solong as the parallel-connected control switch 28 remains in its biasedposition inwvhich it is shown. Furthermore, operation of the switch 27to its upper circuit closing position does not establish an energ zingcircuit, for the elec tromagnetic' switch 24 since switches 23 and 2aare so interlocked that the-switches cannot be energized simultaneously.However, when the cars on the branch track B engage with'thecontrolswitch 28 and op'eratethe latter from its biased position to its uppercircuit-closing position, the energizing circuitot the'operating windingots'witch 23 is interiiipted since both of the I track switches 27and'28 now occupy their respective upper circuit closing positionsConsequentlyp switch 23 is deenegized' and at once'returns tothe lowercircuit closing position," thereby automatically disconnecting thebranch track power conductor T rom the variable}trequencygenerator pIVhenthe lower contacts of switch 23 are closed, an energizing circuittorthe operating winding 'of switch 24*is established which may betraced from the power con-. ductor' T through the conductor 7 eratingwinding of switch 24, and thence in 31, the opparallel circuit throughthe contacts of; the control switches 27 and 28 in their upperpositions. located along the track that one or the other switchalways isengaged by a fsuitablerack carried by each of the cars even though theother switch is released due to thegap in the operating rack between theseveral cars com- It will be understoodthat track switches render theuse of a continuous operating rack along several cars of the trainundesirable. However, by properly locating the two separately operableswitches 27 and '28 along the branch track, the switches may be arrangedto be simultane- The switches 27 and 28 are so B to the power conductorTjof the main operates the contact 26 to directly connect. the powerconductor T oi the branch track track M; Thus, as the first car or" thetrain leaving the branch track Breaches the main track M and thecurrent-collecting device on the car engages with the main track powerconductor T ,v there is no possibility of interconnection between thevariable frequen cy source 11 and the high frequency source 10 throughthe train conductors connecting,

the driving motors of the several cars composing the train. This is dueto the fact that the automatic switch mechanism la is operated under thecontrol of the car operk ated switches 27 and28 to autoinaticallydisConnect the Variable frequt-incy,,,,source 11 from the branch trackpower conductor T and then connect the latter directly to the main trackpower conductor T as the trains of cars leave branch track B and pass onto the main track Vi. .c 5 i A From the foregoing it will be seen thatmy invention insures the safe dispatching of cars i romthe branch trackB to the main track M, since collisions with oncoming cars on the maintrack, as wellasiinterco'nnection between the "powensource supplying thebranch and the main track are effectively revented. v

lVhat I claim as new and desire to secure by Letters Patent of theUnited States is 1. The combination with an electricrailwaysystem'havinga normally deenergized i branch track joining a 'normallyenergized maintrack, otmealns including. a manually operable iswitch mechanism for"energizing the branchtrack towfeed electric motor driven cars therefromto the main track,.and caroperated interlocking devices located on themain track adjacent said branch track and operatively connectedwitlilsaid energizing means for the branch track for preventingenergization of thebranchtrack when'cars are passing on the main track.I V 2.- The combination with an electric railway system having anormally deenergized branch track joining a normally energized maintrack of manually controlled means in: cludingan electrically operatedswitch for energizing the branch track to feed electric motor drivencars therefrom to themain traelgfa car-operated interlocking switchlo-,cated on the main track adjacent said branch track, and connectionscontrolled by said carthe branch track when cars are passing on the maintrack.

3. The combination with an electric railway system having a branch trackand a main track ar'anged to be energized from separate sources, ofautomatic means including an interlocking switch located adjacent thejunction of the branch track with the main track for preventinginterconnection between said power sources when trains oi cars arepassing from one track to the other.

t. The combination with an electric railway system having the powerconductors for adjacenttrack sections energized from separate supplysources, of means including switch mechanism located at the end of oneof said track sections and arranged to be operated by the cars passingtherefrom to the adjacent section for automatically disconnecting thepower conductor of one section from its supply source while the carsbridge the power conductors of the adjacent sections.

5. The combination with an electric railway system having the powerconductors for adjacent track sections energized from separate supplysources, of means including switch mechanism located at the end of oneof said track sections and arranged to be op erated by the cars passingtherefrom to the adjacent section for automatically disconnecting thepower conductors of one section from its supply source and connect thepower conductor of said one section to the supply source of the adjacentsection while the cars bridge the power conductors of the adjacentsections.

6. The combination with an electric railway system having a main trackconnected to be energized from one source, a branch track connected tobe energized from a second source, of means including switch mechanismlocated adjacent the junction of said tracks and arranged to be operatedby the cars passing from the branch track to the main track forautomatically disconnecting the branch track from said second source andthereby prevent interconnection of said sources through the cars passingfrom the branch track to the main track.

7. The combination with an electric railway system having a normallyenergized main track and a. branch track connected to be energized froma separate supply source of (littering electrical characteristics, ofelectrically operated switch mechanism for controlling the connection ofthe branch track with said separate source, a. car-operated controlswitch mechanism located along the branch track adjacentthe main trackto be operated by the cars passing from the branch track to the maintrack, and connections controlled by said car-operated switch mechanismfor effecting operation o'l said electrically operated switch mechanismto disconnect the branch track from said separate source while the carsbridge the main track and the branch track.

8. The combination with an automatic alternating current electricrailway system having a main track normally energized from analternating current source of relatively high frequency, a branch trackarranged to be energized from an alternating current source of variablefrequency, an electromagnetic switch mechanism operable to disconnectthe branch track from said variable frequency source and connect thebranch track to the source of relatively high frequency, a car-operatedcontrol switch located along the branch track adjacent the main track,and connections controlled by said switch for eli ecting operation oi.said electromagnetic switch mechanism to disconnect the branch trackfrom the variable frequency source and connect the branch circuit to thehigh frequency source while the *ars passin from the branch track to themain track bridge the two tracks.

9. The combination with an electric railway system having a branch trackjoining a normally energized main track, oi means for energizing thebranch track from a separate source to feed electric motor driven carstherefrom to the main track, and means including car-operated controlmechanism located along the branch track for disconnecting said separatesource therefrom while cars are passing on the main track and while carsare entering upon the main track from the branch track.

10. The combination with an electric railway system having a normallydeenergized branch track joining a normally energized main track, ofmanually controlled means including electrically operated switchmechanism for energizing the branch track to feed cars therefrom to themain track, a car operated interlocking switch located on the main trackadjacent said branch track. a second car operated interlocking switchlocated on the branch track adjacent said main track, and connectionsseparately controlled by said interlocking switches for preventingoperation of said electrically operated switch mechanism to energize thebranch track when cars are either passing on the main track or cars areentering upon the main track from the branch track.

In witness whereof, I have hereunto set my hand this 25th day of August,1925.

JAMES A. JACKSON.

